Tubular fibrous wall plug



Nov. 6, 1928. 1,690,909 J. J. RAWLINGS l TUBULAR FIBROUS WALL PLUG FiledMarch 26, 1926 TUBULAK CEEE OF LUBK CATLHG MATERIAL klm? Patented Nov.6, 1928.

UNITED STATES PATENT OFFICE.

JOHN JOSEPH BAWLINGS, OF SOUTH KENSINGTON, LONDON, ENGLAND, ASSIGNOR FONE-HALF T0 THE -RAWLPLUG COMPANY LIMITED, OF LONDON, ENGLAND.

TUBULAR FIBROUS WALL PLUG.

Application filed March 26, 1926, Serial No. 97,801, and in GreatBritain March 28, 1925. A'

This invention relates to improvements in tubular fibrous wall plugs ofthe kind comprising a number' of twisted fibrous strands laid side byside and weakly held together,

and the said invention provides improvements whereby the insertion of anail or screw in a plug placed in a hole in a wall, or the like, isfacilitated.

Wall plugs of the type hereinabove referred to, in, which the fibrousstrands are held together by an adhesive or by weak binding strands offibrous material,- as is well known, are expanded by the nail or `screwinserted therein and, in some cases, a

difficulty is experienced in driving in the nail or screw owing to thegripping action exerted thereon, more particularly when the strandscomprised in such plugs are united, or loaded, with adhesive substances,such as '20 glug/bitumen, gum, resin, and the' like, or

a mixture of such adhesive substances, ow` ing to the combined effectsof the heat developed by friction and the pressure exerted in expandingthe plug, increasing the tendency of the nail or screw to adhere to theinterior wall of the plug. A purpose of this invention is to providemeans for minimizing this gripping or sticking of the nail or screw tothe plug into which it is being driven.

According to this invention a tubular wall plug is provided comprising anumber of twisted fibrous strands laid side by side and weakly heldtogether by an adhesive havin a thin layer of lubricant such' asgraphite, steatite, grease or the like applied.

as alining or coating on the interior wall only of the plug.v In oneconvenient arrangement according to this invention, a strip of paper orof textile fabric is im- 40 pregnated with graphite, ste'atite, grease,or other suitable lubricant, or a mixture of these substances, and isarranged as a lining within the plug'.

In another arrangement, in accordance with this invention, thelubricating material in a powdery or pasty form is applied to theinterior of the wall plug without employing a separate'lining materialto hold or support it.

The accompanying drawings illustrate how the said invention can beconveniently and advantageously carried into practice:

In this drawing :-l 4 kFigure 1 is a diagrammatic perspective Figure 2is a diagrammaticview of apparatus suitable for producing a wall plug asshown in Figure 1.

Figure l shows a wall plug comprising a number of twisted fibrousstrands a laid side by side in tubular formation around a tube b ofpaperl or textile fabric impregnated with a suitable lubricant, insertedin the plug during the manufacture of the same by winding, wrapping orfeeding the strip on a mandrel employed to form the tubular wall plug,and the strands comprised in the plug can then be built u on thelubricated strip thus brought to a tu ular form, by any of the knownmethods of manufacture em ployed to produce this type of plug, the stripbeing drawn of the mandrel as the strands are brought together thereon,as will be readily understood, thus providing a continuous lubricatinglining within the tube formed 'by the strands.

The continuous length of tubular material thus formed can be cut toconvenient lengths to form wall plugs. Such wall plugs can be cut from alength of tubular material produced by apparatus, as shown yin Figure 2comprising a reel 0 from which a strip of paper or textile material b'is fed on to a mandrel d around which it is wrapped by passing through asubstantially conical guide tube e. The tube of paper or textile fabricthus formed, impregnated with lubricant, is led between the mandrel anda guide plate f to which the strands a of twisted fibrous material areled from 4spools g. In passing through the annular" or like tube and thestrands are consolidated in a tubular formation.

The mandrel d, as shown in Figure 2, can be made tubular so thatpulverulent, pasty or liquid lubricant can be pumped or fed through the,same into the interior of the tube formed by the strands a brought tothe required formation as they pass between'the guide plate and themandrel before they pass off from the end of the latter.

By mounting the spools g on a rotary head the strands in the tubeproduced can be givstraight in the longitudinal direction o the tube.V

- en a spiral arrangement instead of l ingv bricating linin whichprevents undue fric;

tion between t e nail or vscrew and the interior wall of the tubularplug when the nail or screw is driven therein, and provides a plugespecially suitable for holding screws which may be required to bewithdrawn and replaced in the same hole from time to time..

In use the improved wall plug provided with a lubricant lining `operatesin the same manner as the brous tubular .walplugs heretofore known, thewall plugs being eX panded by the nail or screw driven therein iso as togrip or clanip the nail or screw firmly in the hole in which the plug:has been 7 inserted. The layer' of lubricant thus provided issuiiicient to` facilitate the driving of the' screw or nail into theplug without diminishing the gripping effort exerted on the 1. A tubularwall plug comprising a number of twisted fibrous strands laid side byside and an inner tubular lining of fibrous sheet material impregnatedwith a lubricant.

2. A tubular wall plug comprising a number of twisted fibrous strandslaid side by side and an inner tubular lining of paper impregnated witha lubricant.

3. A tubular wall plug comprising a number of twisted fibrous strandslaid side by side in Contact, and held together in tubular formation byan adhesive cement and a lining of lubricant on the interior wall onlyof the tubular structure.

4:. A tubular/wall plug comprising a number .of twisted fibrous strandslaid side by Qside and weakly held together by an adhesive cement, alubricant on the interior wall of said tubular formation of -ibrousstrands, and means for carrying said lubricant. t JOHN JOSEPH RAWLINGS.

